Book receptacle with collapsible container

Abstract

A book receptacle mounted on wheels forms a movable book storage container. Within the book receptacle is a collapsible container with an upper peripheral edge which is affixed to the upper edge of the support structure of the book receptacle. The collapsible container in an uncollapsed state substantially fills the volume defined by the support structure. A load-responsive support, which is preferably an elastic cord, provides load-responsive support between a first attachment point located at the bottom of the collapsible container and a second attachment point located on the support structure and spaced from the first attachment point so that the collapsible container is held in a substantially collapsed condition when the container is empty and expands to substantially fill the volume defined by the support structure as additional books are added.

I claim: 
     
       1. A book receptacle comprising: (a) a support structure defining a volume open at the top and having an upper peripheral edge;   (b) a collapsible container having a bottom which, in the uncollapsed state, substantially fills the volume defined by the support structure, the collapsible container being open at the top and having an upper peripheral edge which si affixed to the support upper peripheral edge;   (c) an elastic load responsive support, extending from a first attachment point located at the bottom of the collapsible container through a pulley attached to the support structure upper edge over which it turns and extends to a second attachment point located on the support structure and spaced a fixed distance from the pulley, such that the length of the support extending between the pulley and the second attachment point remains fixed as the bottom is depressed, and wherein the collapsible container is held in a substantially collapsed condition by the load responsive support when the container is empty and as the container is loaded with books expands to fill substantially the volume defined by the support structure;   (d) a handle connected to the support structure and adapted to be grasped by a suer for movement of the book receptacle.   
     
     
       2. The book receptacle of claim 1 wherein the collapsible container is a flexible fabric bag. 
     
     
       3. The book receptacle of claim 2 wherein the bottom of the bag is held extended by a frame which holds the bottom of the collapsible gag in a substantially planar configuration. 
     
     
       4. A book receptacle comprising: (a) a support structure defining a volume open at the top and having an upper peripheral edge;   (b) a collapsible container having a bottom which, in the uncollapsed state, substantially fills the volume defined by the support structure, the collapsible container being open at the top and having an upper peripheral edge which is affixed to the support upper peripheral edge;   (c) an elastic cord extending from a first attachment point located at the bottom of the collapsible container through a pulley attached to the support upper edge over which it turns at an angle of approximately 90° and extends to a second attachment point located on the support structure and spaced form the pulley, wherein the cord is attached at its second attachment point to an attachment bracket located on the support upper edge, and wherein the collapsible container is held in a substantially collapsed condition by the cord when the container is empty and as the container is loaded with books expands to fill substantially the volume defined by the support structure;   (d) a handle connected to the support structure and adapted to be grasped by a user for movement of the book receptacle.   
     
     
       5. A transportable book truck comprising: (a) a support structure defining a volume open at the top and having a bottom and an upper peripheral edge;   (b) a collapsible container having a bottom, wherein the container in the uncollapsed state substantially fills the volume defined by the support structure, the collapsible container being open at the top and having an upper peripheral edge which is fixed to the support structure upper peripheral edge;   (c) an elastic load responsive support extending from a first attachment point located at approximately the bottom of the collapsible container through a pulley attached to the support structure upper edge over which it turns and extends to a second attachment point located on the support structure and spaced a fixed distance form the pulley, such that the length of the support extending between the pulley and the second attachment point remains fixed as the bottom is depressed, and wherein the collapsible container is held in a substantially collapsed condition by the load responsive support when the container is empty and as the container is loaded with books expands to fill substantially the volume defined by the support structure; and   (d) a plurality of wheels rotatably mounted to the support structure so that book truck is adapted for easy motion over a surface.   
     
     
       6. The book truck of claim 5 further comprising a handle rigidly mounted to the support structure and adapted for grasping to move the book truck over a surface. 
     
     
       7. The book truck of claim 5 wherein the collapsible container is a flexible fabric bag. 
     
     
       8. The book truck of claim 7 wherein the bottom of the bag is held extended by a frame which holds the bottom of the collapsible bag in a substantially planar configuration. 
     
     
       9. A collapsible bag for a book truck having a support structure with an upper peripheral edge to which a plurality of pulleys are attached and a plurality of elastic load responsive supports, each support extending from an attachment point on the support structure a fixed distance from a pulley, and each load responsive support extends over a pulley and is connected to the bag such that the length of the support extending from the attachment point to the pulley remains fixed as the bag bottom is depressed, the bag comprising: (a) a cloth bag defining a volume open at the top, the bag having four sides, a bottom and an upper edge;   (b) a plurality of fasteners located on the upper edge of the bag adapted to fasten the bag to the book truck support structure;   (c) a cloth surface attached to the bottom of the bag defining a pocket into which may be installed a stiffening frame for the purpose of holding the bottom of the bag substantially flat;   (d) four sleeves attached to the corners of the bag defined by adjacent sides, each sleeve being adapted to containing and guiding a book truck elastic load responsive support; and   (e) reinforcing straps attached to the bag bottom and having attachment points closely spaced from the sleeves for attachment to the elastic load responsive supports running in the sleeves to permit the bag bottom to be supported by the elastic load responsive supports.